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JavaScript

Lee Cockcroft
Lee Cockcroft
5,147 Points
Posted by Lee Cockcroft
Lee Cockcroft
5,147 Points

For loops

Hi All,

Could someone explain something to me please.

For loops with the statement "document.write(i);"

Lists what I want it to list.

However if I "document.getElementByid" (and obviously select a id)

eg

for(var i=0;i<9;i++) {

document.write(i);

}

this works fine, however the below just prints 8?!

for(var i=0;i<9;i++) { document.getElementByid("output").innerHTML=i;

}

Any ideas?

Thanks

2 Answers

andren
andren
28,558 Points
andren
andren
28,558 Points

The second example just prints 8 because you are setting the innerHTML value equal to i in each loop, when you set a value equal to something it replaces whatever was there before. It doesn't add to it. So whatever i is at the end of the loop is what innerHTML will be equal to at the end of the loop, if you use += (which adds a value rather than sets it) instead like this:

for(var i=0;i<9;i++) { 
  document.getElementById("output").innerHTML += i;
}

Then you will end up with the same effect.